#coding=utf8
########################################################################
### ###
### Created by Martin Genet, 2016 ###
### ###
### École Polytechnique, Palaiseau, France ###
### ###
########################################################################
import dolfin
import glob
import numpy
import os
import myFEniCSPythonLibrary as myFEniCS
import myVTKPythonLibrary as myVTK
########################################################################
def fedic(
working_folder,
working_basename,
images_folder,
images_basename,
mesh_folder,
mesh_basename,
images_dimension=3,
k_ref=0,
penalty=0.9,
use_I0_tangent=0,
relax_type="const",
relax_init=0.9,
tol_disp=1e-3,
n_iter_max=100,
print_iterations=0,
continue_after_fail=0,
verbose=1):
if not os.path.exists(working_folder):
os.mkdir(working_folder)
print "Loading mesh…"
mesh = dolfin.Mesh(mesh_folder+"/"+mesh_basename+".xml")
fs = dolfin.VectorFunctionSpace(
mesh=mesh,
family="Lagrange",
degree=1)
dX = dolfin.dx(mesh)
print "Computing quadrature degree…"
degree = myFEniCS.compute_quadrature_degree(
image_filename=images_folder+"/"+images_basename+"_"+str(k_ref).zfill(2)+".vti",
dX=dX,
image_dimension=images_dimension)
print "degree = " + str(degree)
fe = dolfin.FiniteElement(
family="Quadrature",
degree=degree)
print "Loading reference image…"
if (images_dimension == 2):
I0 = myFEniCS.ExprIm2(
filename=images_folder+"/"+images_basename+"_"+str(k_ref).zfill(2)+".vti",
element=fe)
if (use_I0_tangent):
DXI0 = myFEniCS.ExprGradXIm2(
filename=images_folder+"/"+images_basename+"_"+str(k_ref).zfill(2)+".vti",
element=fe)
DYI0 = myFEniCS.ExprGradYIm2(
filename=images_folder+"/"+images_basename+"_"+str(k_ref).zfill(2)+".vti",
element=fe)
elif (images_dimension == 3):
I0 = myFEniCS.ExprIm3(
filename=images_folder+"/"+images_basename+"_"+str(k_ref).zfill(2)+".vti",
element=fe)
if (use_I0_tangent):
DXI0 = myFEniCS.ExprGradXIm3(
filename=images_folder+"/"+images_basename+"_"+str(k_ref).zfill(2)+".vti",
element=fe)
DYI0 = myFEniCS.ExprGradYIm3(
filename=images_folder+"/"+images_basename+"_"+str(k_ref).zfill(2)+".vti",
element=fe)
DZI0 = myFEniCS.ExprGradZIm3(
filename=images_folder+"/"+images_basename+"_"+str(k_ref).zfill(2)+".vti",
element=fe)
else:
assert (0), "images_dimension must be 2 or 3. Aborting."
I0_norm = dolfin.assemble(I0**2 * dX)**(1./2)
print "Defining functions…"
penalty = dolfin.Constant(penalty)
U = dolfin.Function(
fs,
name="displacement")
dU = dolfin.Function(
fs,
name="ddisplacement")
ddU = dolfin.TrialFunction(fs)
V = dolfin.TestFunction(fs)
print "Printing initial solution…"
file_pvd = dolfin.File(working_folder+"/"+working_basename+"_.pvd")
for vtu in glob.glob(working_folder+"/"+working_basename+"_*.vtu"):
os.remove(vtu)
file_pvd << (U, float(k_ref))
print "Defining variational forms…"
if (images_dimension == 2):
I1 = myFEniCS.ExprDefIm2(
U=U,
element=fe)
DXI1 = myFEniCS.ExprGradXDefIm2(
U=U,
element=fe)
DYI1 = myFEniCS.ExprGradYDefIm2(
U=U,
element=fe)
if (use_I0_tangent):
a = penalty * dolfin.inner(dolfin.dot(dolfin.as_vector((DXI0, DYI0)), ddU),
dolfin.dot(dolfin.as_vector((DXI0, DYI0)), V))*dX\
+ (1.-penalty) * dolfin.inner(dolfin.grad(ddU),
dolfin.grad( V))*dX
else:
a = penalty * dolfin.inner(dolfin.dot(dolfin.as_vector((DXI1, DYI1)), ddU),
dolfin.dot(dolfin.as_vector((DXI1, DYI1)), V))*dX\
+ (1.-penalty) * dolfin.inner(dolfin.grad(ddU),
dolfin.grad( V))*dX
b = penalty * dolfin.inner(I0-I1,
dolfin.dot(dolfin.as_vector((DXI1, DYI1)), V))*dX\
- (1.-penalty) * dolfin.inner(dolfin.grad(U),
dolfin.grad(V))*dX
elif (images_dimension == 3):
I1 = myFEniCS.ExprDefIm3(
U=U,
element=fe)
DXI1 = myFEniCS.ExprGradXDefIm3(
U=U,
element=fe)
DYI1 = myFEniCS.ExprGradYDefIm3(
U=U,
element=fe)
DZI1 = myFEniCS.ExprGradZDefIm3(
U=U,
element=fe)
if (use_I0_tangent):
a = penalty * dolfin.inner(dolfin.dot(dolfin.as_vector((DXI0, DYI0, DZI0)), ddU),
dolfin.dot(dolfin.as_vector((DXI0, DYI0, DZI0)), V))*dX\
+ (1.-penalty) * dolfin.inner(dolfin.grad(ddU),
dolfin.grad( V))*dX
else:
a = penalty * dolfin.inner(dolfin.dot(dolfin.as_vector((DXI1, DYI1, DZI1)), ddU),
dolfin.dot(dolfin.as_vector((DXI1, DYI1, DZI1)), V))*dX\
+ (1.-penalty) * dolfin.inner(dolfin.grad(ddU),
dolfin.grad( V))*dX
b = penalty * dolfin.inner(I0-I1,
dolfin.dot(dolfin.as_vector((DXI1, DYI1, DZI1)), V))*dX\
- (1.-penalty) * dolfin.inner(dolfin.grad(U),
dolfin.grad(V))*dX
else:
assert (0), "images_dimension must be 2 or 3. Aborting."
# linear system
A = None
B = None
if (use_I0_tangent):
A = dolfin.assemble(a, tensor=A)
print "Checking number of frames…"
n_frames = len(glob.glob(images_folder+"/"+images_basename+"_*.vti"))
print "n_frames = " + str(n_frames)
assert (abs(k_ref) < n_frames)
k_ref = k_ref%n_frames
n_iter_tot = 0
for forward_or_backward in ["forward", "backward"]: # not sure if this still works…
print "forward_or_backward = " + forward_or_backward
if (forward_or_backward == "forward"):
k_next_frames = range(k_ref+1, n_frames, +1)
elif (forward_or_backward == "backward"):
k_next_frames = range(k_ref-1, -1, -1)
print "k_next_frames = " + str(k_next_frames)
for k_next_frame in k_next_frames:
print "k_next_frame = " + str(k_next_frame)
if (print_iterations):
if (os.path.exists(working_folder+"/"+working_basename+"-frame="+str(k_next_frame).zfill(2)+".pdf")):
os.remove(working_folder+"/"+working_basename+"-frame="+str(k_next_frame).zfill(2)+".pdf")
file_dat_iter = open(working_folder+"/"+working_basename+"-frame="+str(k_next_frame).zfill(2)+".dat", "w")
file_pvd_iter = dolfin.File(working_folder+"/"+working_basename+"-frame="+str(k_next_frame).zfill(2)+"_.pvd")
for vtu in glob.glob(working_folder+"/"+working_basename+"-frame="+str(k_next_frame).zfill(2)+"_*.vtu"):
os.remove(vtu)
file_pvd_iter << (U, 0.)
print "Loading image and image gradient…"
if (images_dimension == 2):
I1.init_image( filename=images_folder+"/"+images_basename+"_"+str(k_next_frame).zfill(2)+".vti")
DXI1.init_image(filename=images_folder+"/"+images_basename+"_"+str(k_next_frame).zfill(2)+".vti")
DYI1.init_image(filename=images_folder+"/"+images_basename+"_"+str(k_next_frame).zfill(2)+".vti")
elif (images_dimension == 3):
I1.init_image( filename=images_folder+"/"+images_basename+"_"+str(k_next_frame).zfill(2)+".vti")
DXI1.init_image(filename=images_folder+"/"+images_basename+"_"+str(k_next_frame).zfill(2)+".vti")
DYI1.init_image(filename=images_folder+"/"+images_basename+"_"+str(k_next_frame).zfill(2)+".vti")
DZI1.init_image(filename=images_folder+"/"+images_basename+"_"+str(k_next_frame).zfill(2)+".vti")
else:
assert (0), "images_dimension must be 2 or 3. Aborting."
print "Running registration…"
k_iter = 0
relax = relax_init
while (True):
print "k_iter = " + str(k_iter)
n_iter_tot += 1
# linear system
if not (use_I0_tangent):
A = dolfin.assemble(a, tensor=A)
#print "A = " + str(A.array())
if (k_iter > 0):
if (k_iter == 1):
B_old = B.copy()
elif (k_iter > 1):
B_old[:] = B[:]
#print "B_old = " + str(B_old[0])
B = dolfin.assemble(b, tensor=B)
#print "B = " + str(B[0])
dolfin.solve(A, dU.vector(), B)
#print "dU = " + str(dU.vector().array())
# relaxation
if (relax_type == "aitken") and (k_iter > 0):
if (k_iter == 1):
dB = B - B_old
elif (k_iter > 1):
dB[:] = B[:] - B_old[:]
relax *= (-1.) * B_old.inner(dB) / dB.inner(dB)
print "relax = " + str(relax)
# solution update
U.vector()[:] += relax * dU.vector()[:]
#U.vector().axpy(relax, dU.vector())
if (print_iterations):
#print "U = " + str(U.vector().array())
file_pvd_iter << (U, float(k_iter+1))
# displacement error
dU_max = numpy.linalg.norm(dU.vector().array(), ord=numpy.Inf)
U_max = numpy.linalg.norm(U.vector().array(), ord=numpy.Inf)
err_disp_abs = max(dU_max, U_max)
U_norm = numpy.linalg.norm(U.vector().array())
err_disp_rel = dU_max/U_norm
print "err_disp_abs = " + str(err_disp_abs)
print "err_disp_rel = " + str(err_disp_rel)
# image error
I1I0_norm = dolfin.assemble((I1-I0)**2 * dX)**(1./2)
err_im = I1I0_norm/I0_norm
print "err_im = " + str(err_im)
if (print_iterations):
file_dat_iter.write(" ".join([str(val) for val in [k_iter, err_disp_abs, err_disp_rel, err_im]])+"\n")
# exit test
if (err_disp_rel < tol_disp) or (err_disp_abs < tol_disp):
print "Nonlinear solver converged…"
success = True
break
if (k_iter >= n_iter_max-1):
print "Warning! Nonlinear solver failed to converge…"
success = False
break
# increment counter
k_iter += 1
if (print_iterations):
os.remove(working_folder+"/"+working_basename+"-frame="+str(k_next_frame).zfill(2)+"_.pvd")
file_dat_iter.close()
os.system("gnuplot -e \"set terminal pdf; set output '"+working_folder+"/"+working_basename+"-frame="+str(k_next_frame).zfill(2)+".pdf'; set logscale y; plot '"+working_folder+"/"+working_basename+"-frame="+str(k_next_frame).zfill(2)+".dat' using 1:3\"")
if not (success) and not (continue_after_fail):
break
print "Printing solution…"
file_pvd << (U, float(k_next_frame))
if not (success) and not (continue_after_fail):
break
print "n_iter_tot = " + str(n_iter_tot)
os.remove(working_folder+"/"+working_basename+"_.pvd")
return success